1. Field of the Invention
The present invention relates to a jewelry clasp and especially relates to a technique that improves aesthetic appearance and convenience for users as a result of, for example, two clasps which are individually provided at the two ends of a pearl necklace being capable of employing a state in which the clasps individually embrace pearls and being capable of employing a state in which the clasps engage with each other.
2. Description of the Related Art
A typical example of a pearl necklace includes one of a type having clasps (clamps) at the two ends thereof, the clasps being able to individually embrace pearls.
In this type of pearl necklace, one clasp embraces any one of pearls that are arranged in series in the form of a string, and the other clasp embraces any one of the other pearls, so that the length of the pearl necklace is capable of being adjusted or so that the appearance of the necklace is capable of being changed when the necklace is worn [for example, see Japanese Unexamined Utility Model Application Publication No. 4-40484 (FIGS. 7 to 9 thereof)].
Furthermore, in some types of clasp that embraces the pearl, two clasps are used and then are connected to each other, so that the shape of a pearl necklace that is worn around a neck is capable of being variously changed (for example, see Japanese Unexamined Patent Application Publication Nos. 63-10736 and 2007-275398).
However, in the technique disclosed in Japanese Unexamined Utility Model Application Publication No. 4-40484 (FIGS. 7 to 9 thereof), the two clasps that are individually provided at the two ends of a pearl necklace are not capable of being connected to each other.
Accordingly, in the case where a pearl necklace is set so as to have the greatest length, the pearls of the necklace extend in the form of double lines as illustrated in disclosed FIG. 9, the pearls being arranged in series between the two clasps in the form of a string. Therefore, aesthetic appearance is not capable of being improved.
In addition, in the techniques disclosed in Japanese Unexamined Patent Application Publication Nos. 63-10736 and 2007-275398, the two clasps are connected to each other by using a retaining ring. Therefore, aesthetic appearance is poor, and furthermore the retaining ring is not easily removed and attached, resulting in decreased convenience for users.